You've been told countless times it's a phishing e-mail. You can either listen and delete it, login and possibly lose your account or waste your day searching around B.NET looking for a download link for your D3 BETA which won't be there.

If the Prince of Saudia Arabia ever offers you $10m to help him transfer money, I would certainly take it.

It is not a real e-mail, this is my account, WITHOUT Diablo 3 (but the annual pass): (this is translated, since 'my account' is not in English)

YOUR GAME ACCOUNTS
Diablo III®
Pre-Download not available at the moment
World of Warcraft®: Cataclysm
[XXXXXX]
Europe (EU)
World of Warcraft®: Battle Chest®
[WoW1]
United States (US)
World of Warcraft®: Cataclysm
[WoW1]
Public Test Realm (PTR)
World of Warcraft®
Europe (EU)
Play Free

Then try clicking the D3 icon in your game summary. Why do people have such a hard time with this crap. If it's there click on it, but don't ever email out your PW it's really common sense at this point.

YOUR GAME ACCOUNTS
DIABLO IIIDiablo III® (Coming Soon)
Visit the Community Site.
WORLD OF WARCRAFT
World of Warcraft®: Cataclysm
[**********]
Americas & Oceania (US)
World of Warcraft®: Cataclysm
[WoW1]
Public Test Realm (PTR)

Copied from my battle.net page

I should also note, 90% of the time, phishing emails go into my spam folder and it warns me when I open 1.

That just means that the digital download is coming soon. It's probably just a result of the annual pass being released. People that got the annual pass show "Pre-download not yet available" and accounts without it say Diablo 3 is coming soon.

A beta invite would be a separate listing saying something to the effect of "Diablo 3: Beta [D3]"